The background description provided herein is for the purpose of generally presenting the context of the present invention. The subject matter discussed in the background of the invention section should not be assumed to be prior art merely as a result of its mention in the background of the invention section. Similarly, a problem mentioned in the background of the invention section or associated with the subject matter of the background of the invention section should not be assumed to have been previously recognized in the prior art. The subject matter in the background of the invention section merely represents different approaches, which in and of themselves may also be inventions.
There have been enormous increases in the global demand for electricity today. The electricity system is based primarily on coal-fired power stations, natural gas fired power stations and nuclear plants which operate continually and cannot be turned on and off at short notice. Since electricity cannot be stored on a large scale, it must be produced and brought to consumers at the very time it is needed. Electricity supplies are usually in shortage in-peak hours (e.g., daytime). On the other hand, the electricity supplies in off-peak time (e.g., overnight) are abundant.
To make use of the continual power, the power companies try to encourage people to use electricity overnight. Supplying in-peak electricity is costly, thus prices are set to incite consumers to shift their load outside peak hours, making off-peak power cheaper. Here are some of the main reasons for the high cost of in-peak electricity. Transmission bottlenecks: most generating plants are far from cities; if the peak demand is larger than the capacity of transmission lines bringing electricity to cities, suppliers must use closer power generators during peak hours—most often very expensive gas-fired plants. Transmission equipment cost: power lines are very expensive and must be large enough to sustain the maximum peak demand; shifting demand to off-peak hours delays installation of new transmission equipment by electricity suppliers and reduce their operating costs. Off-peak electricity may also be cheaper because some types of generators, like nuclear plants, must produce maximum power 24 hours a day during their entire lifespan; lots of electricity thus gets produced off-peak and must be sold, even at lower prices. It would gain a great deal of relevance to solving problems of energy shortage and reducing environmental pollution produced by the electricity generation if the electricity generated in the off-peak time could be massively stored and transmitted back to electricity grids at need.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.